I've kept many male and female Betta in the past, but this is my first half moon double tail! I've only had Sean for about a month, but he has been acting very unusual the past three days and I cannot tell if something is wrong with him or if this is just a quirk of the “breed”.

Since Friday, he has been working very hard – very very hard – on making a bubble nest. He's been zipping around, flaring his gills, displaying and gathering bubbles which I am quite used to. What I'm not used to is that he has started laying on his side. It is always at the surface of the water and always in a corner (typically near the nest).

On Saturday, his belly was swollen after a full day of working on the nest and he was having a hard time swimming and keeping his body straight. I thought it was a bit of swollen bladder disease since he had eaten brine shrimp the last few days, so I gave him a pea and he was fine by Sunday. We went through Sunday without incident, then I get home today to find him laying on his side again. His belly is not swollen and I don't know what's wrong.

Is is usual for double tails to do this? I've never had a Betta just lounge on it's side. He only started doing this after he began working on the nest – so I'm not sure what to make of it. Again, he's not bloated, he has no signs of any other diseases, his color/fins have not changed and the snail he lives with isn't acting abnormal...it's only the way he's acting and I'm completely baffled!

Here are some specifics on my tank/feeding/care, just in case:

I have a 5 gallon tank with a filter that is kept at 75 degrees. The only other room mate is a snail. There are no live plants, but he has plenty of places to hide. I mix out feeding him brine shrimp, blood worms and pellets and give him a bit of pea now and then. I do 25% water changes once a week and dechloronate the tap water before adding it to the tank.

I would increase to 50% water changes a week in a 5g, and make sure it includes using a siphon to clean the gravel and not just taking water off the top. This is for a fully cycled tank though.. is your tank fully cycled? What's the ammonia, nitrite and nitrate levels? I suggest owning a drops kit for these if you do not want to do weekly 100% changes.

He's also cold.. do you not have a heater? I would increase his temperature to between 78-80, slowly no more than a degree per hour. You should also use a thermometer that stays in the tank to determine temp.

At this point I'd go ahead and do a 50% change now including gravel siphon and replace with preheated water (just run the tap to match your water and use the thermometer in the tank to know) and preconditioned (If you don't do this normally you can pick up gallon water jugs at the grocery store and rinse them well in hot water but no chems, or use plastic buckets from the hardware store rinsed well. I use gallon jugs and a 5g bucket from home depot). See if that doesn't help..

Housing
What size is your tank? 5 gallon
What temperature is your tank? 75degrees
Does your tank have a filter? Yes
Does your tank have an air stone or other type of aeration? No
Is your tank heated? No
What tank mates does your betta fish live with? 1 snail

How often do you feed your betta fish? Typically three days on, three days off
Maintenance
How often do you perform a water change? 25% every week
What percentage of the water do you change when you perform a water change? 25%
What type of additives do you add to the water when you perform a water change? I dechlorinate the water

Water Parameters:
Have you tested your water? If so, what are the following parameters?No

Ammonia:
Nitrite:
Nitrate:
pH:
Hardness:
Alkalinity:

Symptoms and Treatment
How has your betta fish's appearance changed? No
How has your betta fish's behavior changed? Yes, he's laying on his side under his bubble nest, but it is not constant
When did you start noticing the symptoms? Two days ago
Have you started treating your fish? If so, how? No
Does your fish have any history of being ill? No
How old is your fish (approximately)? I'm not sure, I've only had him a month.

He cannot see other Bettas - he is the only one I have right now. I don't currently have a heater, but I do have a thermometer in the tank. It stays at 75 degrees in that room, but I will look into getting him a heater ASAP.

I guess I should mentioned that I did just have algae show up for the first time in the tank. It grew on the glass and on a few of the objects in the tank as well. I cleaned it off the glass, but left a bit behind for the snail. This happened a few days before my little baby starting acting so weird.

He really should only need one fast day a week. Some people do two days, but I wouldn't go 50/50 feed.

Snails are pretty dirty. You may even need twice weekly water changes of 25% and 50% or even two 50%s, assuming it's all cycled.

I would go get a drops kit for ammonia, nitrite and nitrate and test, if you can afford it. It's a really good thing to have on hand and I wouldn't suggest running a tank without 100% changes without one. This one is popular and easy to find: http://www.amazon.com/API-Freshwater.../dp/B000255NCI

Algae means you have a light.. that light may make the glass more reflective for him. Since you don't have live plants, I'd turn it off. Make sure you are only leaving it on about 8 hours, regardless.

Okay. That's a good plan. Make sure to get a drops kit and not strips. Also be careful with the instructions if you get the API kit.. there's a lot of shaking that's necessary, both of tubes and bottles to get accurate results.

When you get the heater I would run it 24 hours in similar size container with in tank thermometer to make sure it's working right and will hold not only an appropriate temp but a stable temp. then you can start to acclimate your buy to a slightly higher temp at no more than 1 degree per hour

I wasn't able to get a proper kit, but I did get pH test strips (yikes, I know). My water is alkaline so I will need to adjust that and see what else I can dig up tomorrow. Thanks so much for your help.

I wouldn't try adjusting the oh too much because often that's more dangerous to the fish. If its between 6.4 and 8.0 a Betta can get used to it easily. Lowering pH is usually hard to do as it is directly related to the water hardness.

He is a bit more active this morning, but I noticed his swim bladder is swollen again. This happened on Saturday. So far, it looks like he is struggling to swim upright, but keeps turning on his side. He has been propping himself up against objects in the tank to steady himself.

I do have the heater on, but will wait a bit later to change/add anything to the water. I don't want to freak him out too much. I know the water in the tank is hard - do you think I should try to do some distilled water when I do my next change?